Thread drawing machine



Nov. 5, 1935. A. THOMAS THREAD DRAWING MACHINE Filed May 25, 1954 2Sheets-Sheet l Nov. 5, 1935.

A. THOMAS 2,019,586

THREAD DRAWING MACHINE Filed May 23, 195:4 2 Sheets-Sheet 2 PatentedNov. 5, 1935 UNITED ST ENT 'FFEQ Anker-Werke Germany Aktiengesellschaft,

Bielefeld,

Application May 23, 1934, Serial No. 727,173 In Germany July 10, 1933 11Claims.

The instant invention relates to an improvement in thread drawingmachines, more particularly of the type disclosed in Patent No. 1,984,-501, issued December 18, 1934. This invention relates in particular tothe simplification of the drive for the special presser feet for athread drawing machine, disclosed in the above patent, and to thecooperation of these special presser feet with the piercing blade.

Theinvention consistsparticularly in forming the'rod for the specialpresser feet as a hollow body which guides the rod of the piercingblade. One or more open recesses-are provided in the hollow body for theconnection of the-crank arm with the rod, which effects thereciprocating movement of the piercing blade. In accordance with theinvention, the curved-groove disc, which effects the actuation of thespecial presser feet, is united with the crank for driving the piercingblade in a single cast piece. A roller, fixed upon the hollow shaft ofthe special presser feet, engages directly in the curved groove of thecam disc.

By the above arrangement, a complete series of advantages are obtained.In the first place, certain parts which are necessary for the drive ofthe machine in accordance with the aforesaid Patent No. 1,984,501, areeliminated. This is the case in particular with the inconvenienttransmission shaft. lying outside of the sewing machine arm, andextending from the curved groove to the presser foot rod, as well aswith crank arm fixed upon this transmission shaft. Aside from this, thecoaxial disposition of the rod for the piercing blade and the rod of thespecial presser feet makes possible an equilateral and symmetricalformation of the U-shaped yoke which carries the legs of the specialpresser feet, which in turn influences favorably the division of thepressure and the uniformity of the tension imposed upon the material. Bythe elimination of all special external bearings for the transmissionparts and by the placement of all the driving parts upon the inside ofthe arm, there results the possibility of using a machine arm of theusual dimensions for thread drawing machines.

An embodiment of the invention is illustrated in the accompanyingdrawings, wherein Fig. l is a front view of the machine with certainparts shown in section,

Fig. 2 is a left end view thereof,

Fig. 3 is a left end view of the machine with the cover removedtherefrom, and

Fig. 4 is a sectional view along line IVIV of Fig. 3.

In Fig. 1 is shown the sewing machine arm I containing the usual driveshaft 2, upon which is fixed a unitary cast body 3, 4, 5. Portion 3 ofthis cast body corresponds to the crank arm, and portion 4, to the crankpin. The crank arm 3 5 is directly united in a single piece, by means ofthe crank pin a, to a grooved cam disc 5. A' roller 1, carried upon aclamping piece 8, engages in the groove 6 of the cam disc 5, theclamping element 8 being attached to the hollow member 9. 10 This hollowmember or presser-bar 9, which is substituted for the massive rod forthe special presser feet in the machine disclosed in the above patent,is guided at its lower end directly in the machine arm, and at its upperend, ina special bush it. This hollow member carries an equilaterallyformed U-shaped yoke H, in the legs 52 of which are inserted the presserfeet or lugs E3 of resilient material, such as rubber. The U- shapedyoke H with its legs 52 embraces the presser feet of the normalpresser-bar 26.

The reciprocating rod i5, carrying the piercing blade it, is arrangedinside of the hollow member 9. Upon the rod i5 is engaged, in knownmanner, a connecting rod 58 by means of a split 25 block it. In order toenable the bearing head of the connecting rod 8 to be mounted upon thecrank pin 5, the bearing head 2i is split or divided in known manner. Inorder" to enable the movement of the split block l9 through the hollowbody 9 and an unhindered relative movement of the body 9 and the rod 55,the mid-portion of the hollow body 9 is enlarged and is open at eitherthe inner side alone or on both sides, thereby resulting in across-section, as shown in Fig. 4.

A guiding lug or projection 2| is connected with the clamping piece 8upon the hollow body 9, which slides in a slot 22 in the cover 23. Thisarrangement eliminates rotative movement of the hollow member 9 whichwould interfere with its up and down movement and cause the roller 7 tojam in the cam groove 5.

By the arrangement in accordance with the invention, all the drivingelements may be disposed within the sewing machine arm; and, by theelimination of all the exterior bearing projections, it is possible touse as well a machine arm of the usual dimensions for thread drawingmachines.

The machine as described works in the following manner: The normalpresser-bar is pressing on the material. The special presser-bar goesdown before the blade pierces the material. Its rubber feet are spreadin meeting the material, and in this manner tightly draw the materialbefore the blade pierces.

What I claim is:

1. In a machine of the class described, presser feet, a piercing tool, ahollow presser-bar connected with said presser feet, a reciprocating rodfor said piercing tool fitted within said hollow presser-bar, and meansfor actuating said hollow presser-bar and reciprocating rod.

2. In a machine of the class described, presser feet having resilientextremities, a piercing tool, a hollow presser-bar connected with saidpresser feet, a reciprocating rod for said piercing tool fitted withinsaid hollow presser-bar, and means for actuating said hollow presser-barand reciprocating rod.

3. In a machine of the class described, presser feet, a piercing tool, ahollow presser-bar connected with said presser feet, a reciprocating rodfor said piercing tool fitted within said hollow presser-bar, means foractuating said rod comprising a drive shaft and connections between saiddrive shaft and rod, and at least one opening in said hollow presser-barfor permitting the movements of said connections.

4. In a machine of the class described having a head, presser feet, apiercing tool, a hollow presser-bar in said head connected with saidpresser feet, a reciprocating rod for said piercing tool fitted withinsaid hollow presser-bar, and unitary driving means wholly within saidhead for actuating said hollow presser-bar and reciprocating rod.

5. In a machine of the class described having a head, presser feet, apiercing tool, a hollow presser-bar in said head connected with saidpresser feet, a reciprocating rod for said piercing tool fitted withinsaid hollow presser-bar, and driving means wholly within said head foractuating said hollow presser-bar and reciprocating rod comprising adrive shaft, an integral unit fixed to said drive shaft consisting of acrank arm, a crank pin for reciprocating said rod, and a cam disc fordriving said hollow presser-bar.

6. In a machine of the class described having a head, presser feet, apiercing tool, a hollow presser-bar in said head connected with saidpresser feet, a reciprocating rod for said piercing tool fitted withinsaid hollow presser-bar, and driving means wholly within said head foractuating said hollow presser-bar and reciprocating rod comprising adrive shaft, an integral unit fixed to said drive shaft consisting of acrank arm, a crank pin and a grooved cam disc,

a roller on said hollow presser-bar engaging said cam disc and aconnecting rod between said crank pin and reciprocating rod.

7. In a machine of the class described, presser feet for stretching thematerial, a piercing tool, 5

an equilateral yoke for carrying said presser feet, a hollow presser-barconnected with said yoke, a reciprocating rod for said piercing toolfitted within said hollow presser-bar and passing through the centralportion of said yoke, and 10 means for actuating said hollow presser-barand rod 8. In a thread drawing machine, a conventionally dimensioned armadapted for household sewing machines terminating in a hollow head, 15presser feet for stretching the material, a piercing blade, a hollowpresser-bar in said head connected with said presser feet, areciprocating rod for said piercing blade fitted within said hollowpresser-bar, and unitary driving means whol- 20 ly within said head foractuating said hollow presser-bar and reciprocating rod.

9. In a machine of the class described having a head, a cover for saidhead having a slot therein, presser feet, a piercing tool, a hollowpresser-bar 25 in said head connected with said presser feet, areciprocating rod for said piercing tool fitted within said hollowpresser-bar, driving means wholly within said head for actuating saidhollow presser-bar and reciprocating rod comprising 3 a drive shaft, anintegral unit fixed to said drive shaft consisting of a crank arm, acrank pin and a grooved cam disc, a roller on said hollow presser-barengaging said cam disc, a connecting rod between said crank pin andreciprocating 3;,

rod, and a guiding lug on said hollow presserbar slidable within theslot in said cover.

10. In a thread drawing machine, a normal presser-bar, presser feet onsaid normal presserbar constantly pressing against the material, a 40second hollow presser-bar, an equilateral yoke on said secondpresser-bar terminating in presser feet, said last-mentioned presserfeet embracing symmetrically said first-mentioned presser feet,

a piercing tool, a reciprocating rod for said piercing tool within saidsecond and means for imparting vertically reciprocating movements tosaid second presser-bar and said rod during the machine operation.

11. The machine as claimed in claim 10, where- 50 in the last-mentionedpresser feet have resilient extremities arranged in parallel to thefirstmentioned presser feet.

AUGUST THOMAS.

hollow presser-bar,

